The cacatuids (Cacatuidae G.R.Gray, 1840) are a family of birds belonging to the order Pésiformiformes.
The name cacatua derives from the Malay name of these birds, kaka (k) tua (compound form of kaka, “parrot”, + tuwah, or “older sister”, from the words kakak, “sister”, + yours, “old” ).
The cockatoos share many aspects with the other parrots, including the characteristic curved beak and the zygodactyl foot, with two fingers behind and two more in front. They differ, however, in a number of characteristics, including the spectacular erectile crest on the head, the presence of a gall bladder and some other anatomical details, and the lack of composite feathers with a Dyck texture, a feature that is at the origin of the blues and bright greens of the Psittacidae.
The cockatoos have a narrower range than the Psittacidae, being found in nature only in Australia and nearby islands. Eleven of the 21 species live in the wild only in Australia, while seven species live in Indonesia, New Guinea and other islands in the South Pacific. Three species are found both in New Guinea and in Australia.
